• Title/Summary/Keyword: Community composition

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Effects of Short-Term Soil Tillage Management on Activity and Community Structure of Denitrifiers under Double-Cropping Rice Field

  • Tang, Haiming;Li, Chao;Cheng, Kaikai;Shi, Lihong;Wen, Li;Xiao, Xiaoping;Xu, Yilan;Li, Weiyan;Wang, Ke
    • Journal of Microbiology and Biotechnology
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    • v.30 no.11
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    • pp.1688-1696
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    • 2020
  • Soil physical and chemical characteristics, soil potential denitrification rates (PDR), community composition and nirK-, nirS- and nosZ-encoding denitrifiers were studied by using MiSeq sequencing, quantitative polymerase chain reaction (qPCR), and terminal restriction fragment polymorphism (T-RFLP) technologies base on short-term (5-year) tillage field experiment. The experiment included four tillage treatments: conventional tillage with crop residue incorporation (CT), rotary tillage with crop residue incorporation (RT), no-tillage with crop residue retention (NT), and rotary tillage with crop residue removed as control (RTO). The results indicated that soil organic carbon, total nitrogen and NH4+-N contents were increased with CT, RT and NT treatments. Compared with RTO treatment, the copies number of nirK, nirS and nosZ in paddy soil with CT, RT and NT treatments were significantly increased. The principal coordinate analysis indicated that tillage management and crop residue returning management were the most and the second important factors for the change of denitrifying bacteria community, respectively. Meanwhile, this study indicated that activity and community composition of denitrifiers with CT, RT and NT treatments were increased, compared with RTO treatment. This result showed that nirK, nirS and nosZ-type denitrifiers communities in crop residue applied soil had higher species diversity compared with crop residue removed soil, and denitrifying bacteria community composition were dominated by Gammaproteobacteria, Deltaproteobacteria, and Betaproteobacteria. Therefore, it is a beneficial practice to increase soil PDR level, abundance and community composition of nitrogen-functional soil microorganism by combined application of tillage with crop residue management.

Analysis of the Characteristics of Spatial Composition in Rural Village - Focused on Godeumi Village, Myeongsim Experience Village, Ohbaksa Village - (농촌마을 공간구성에 관한 특성 분석 - 고드미녹색마을, 명심체험마을, 오박사마을을 중심으로 -)

  • Jeong, Da-Yeong;Rhee, Shin-Ho
    • Journal of Korean Society of Rural Planning
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    • v.19 no.4
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    • pp.329-338
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    • 2013
  • The purpose of this study is that suggest space composition in rural village so that it can had foundations for Activation of regional community by analysis and re-organization of rural community places based on regionality and historicity. First, this study have been investigated about changes of overall space configuration and community places that has been lost or were ongoing in rural village. Factors of changes were changes in lifestyle, rural policy, social and political system, economic principles and ect. Therefore, This study focused on understanding basic principles of rural village space configuration and inherited it. Second, basic principle of the space configuration of rural village were entryway and center that improve community cohesion in the community space. This study figured out improving of "Ma-Dang" and functional mix-use community hall was important for more efficient management. Third, This study set direction according to characteristic of space configuration of each village and suggested detail plans.

Community Structure and Habitat Environment of Genus Liriope Group in Korea (한반도 맥문동속 집단의 자생지 생육환경과 군락구조)

  • Song, Hong-Seon;Lee, Jung-Hoon;Kim, Seong-Min;Shin, Dong-Il;Kim, Chang-Ho;Koo, Han-Mo;Park, Chung-Berm;Park, Yong-Jin
    • Korean Journal of Medicinal Crop Science
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    • v.19 no.1
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    • pp.24-30
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    • 2011
  • This text was analyzed and investigated the vegetation and floristic composition by cluster analysis and classification of phytosociological method, to evaluate the species composition, habitat environment and community structure of Liriope platyphylla and Liriope spicata group in Korea. The southeast slope gradient of the habitat of L. platyphylla and L. spicata was 6.7 to 8.4%, and the habitat altitude of L. platyphylla (41.0 m), L. spicata (114.9 m) was different. Habitat distribution of L. spicata was broader than L. platyphylla. Appearing plants of L. platyphylla and L. spicata group was 58 taxa, 99 taxa, respectively, and Coverage of tree layer was 87.5%, 92.5% respectively. In genus Liriope group, the highest appearing frequency of plant grow in the moist valley as Quercus serrata. Thus, plants of genus Liriope growth was better in moist shade. The vegetation of L. platyphylla group was classified into Quercus serrata community, Castanopsis sieboldii community, Pinus densiflora community and Pinus thunbergii community, and the Liriope spicata group was classified into Quercus serrata community, Quercus alien community, Quercus acutissima community, Prunus verecunda community, Robinia pseudoacacia community, Pinus densiflora community and Pinus thunbergii community. In genus Liriope group, Quercus serrata and Pinus densiflora communities was the closest the similarities.

International Comparison of Food Composition Table (한국, 미국, 일본의 식품성분표 비교)

  • 최정숙;전혜경;박홍주
    • The Korean Journal of Community Living Science
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    • v.12 no.2
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    • pp.119-135
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    • 2001
  • This study was conducted to compare the composition table of Korean food with that of foreign food. Analysis was made for Korean food composition table($5^{th}$ revision), Korean food composition table in Appendix of Recommended Dietary Allowances for Korean(6$^{th}$ th/ edition), Standard tables of food composition in Japan($5^{th}$ revised edition) and USDA Composition of Foods - Raw, Processed, Prepared. The method of content analysis was applied for this study and such differences were pointed out as the classification of food items, food items enlisted, the content unit of food and food components presented etc. To improve Korean food composition table, new food items and components should be added and old food items be eliminated based on the change of people's food consumption pattern. Also analysis for the domestic foods consumed by local people should be accomplished rather than borrowing foreign country's data.

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The Evaluation of Correlation between Disturbance Intensity and Stand Development by Natural Forest Community Type Classification (자연림 군집형 분류에 의한 교란의 정도와 임분 발달 사이의 관련성 검토)

  • Kim, Ji Hong;Hwang, Kwang Mo;Kim, Se Mi
    • Journal of Forest and Environmental Science
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    • v.29 no.3
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    • pp.219-225
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    • 2013
  • The correlation between disturbance intensity and stand development was evaluated on the basis of natural forest community type classification in areas of Baekhaksan (more disturbed area) and Hwangaksan (less disturbed area). The vegetation data were collected by point-centered quarter sampling method, and they were subjected to cluster analysis for classifying community types and to analysis of species composition and species diversity for reviewing ecological characteristics. By the method of cluster analysis, natural forests of Baekhaksan were classified into Quercus forest community, Pinus densiflora community, Q. variabilis community, and Q. mongolica community. Those of Hwangaksan were divided into P. densiflora community, Q. mongolica community, Q. forest community, and Mixed mesophytic community. It is presumed that more developed and less disturbed forest area shows multiple species community pattern and more diversified structure than less developed and more disturbed forest area. In Korean peninsula, the abundance of red pine may play an important indicator to estimate the developmental pattern of the forest after artificial disturbance. The overall evaluation indicated that less disturbed Hwangaksan area had more developed stand pattern with mixed mesophytic community, more complicated species composition, and higher species diversity than Baekhaksan area.

Vegetation Structure of Peucedanum japonicum Thunb. Community in East Seaside of South Korea (우리나라 동해변 식방풍 군락의 식생구조)

  • Shin, Dong-Il;Song, Hong-Seon;Yoon, Seong-Tak;Kim, Seong-Min
    • Korean Journal of Medicinal Crop Science
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    • v.14 no.6
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    • pp.347-353
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    • 2006
  • This study was conducted to evaluate the vegetation structure and ordination of the Peucedanum japonicum Thunb. community by the Phytosociological method, floristic composition table on east coast of South Korea. The vegetation of Peucedanum japonicum Thunb. community was classified into 2 communities such as the Aster Spathulifolius community and the calystegia soldanella-Artemisia princeps community. Vegetation of the Peucedanum japonicum Thunb. community with the Aster spathulifolius community was shown southward, whereas vegetation of Peucedanum japonicum Thunb. community with the calystegia soldanella-Artemisia princeps community was shown northward from the base line of Pohang at North latitude of 36" 05'. Accordingly, the Peucedanum japonicum Thunb. community was grown commonly with the Aster spathulifolius community southward of the base line of Pohang, whereas it was grown commonly with the calystegia soldanella-Artemisia princeps community northward on the east coast. All environmental conditions of habitat taken together, the optimum habitat of Peucedanum japonicum Thunb. was at Ulsan geographically and the middle region of sea cliff topography, and was suitable for alkali. sandyloam.

Vertical and longitudinal variations in plant communities of drawdown zone of a monsoonal riverine reservoir in South Korea

  • Cho, Hyunsuk;Marrs, Rob H.;Alday, Josu G.;Cho, Kang-Hyun
    • Journal of Ecology and Environment
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    • v.43 no.2
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    • pp.271-281
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    • 2019
  • Background: The plant communities within reservoir drawdown zones are ecologically important as they provide a range of ecosystem services such as stabilizing the shoreline, improving water quality, enhancing biodiversity, and mitigating climate change. The aim of the study was therefore to identify the major environmental factors affecting these plant communities within the drawdown zone of the Soyangho Reservoir in South Korea, which experiences a monsoonal climate, and thereafter to (1) elucidate the plant species responses and (2) compare the soil seedbank composition along main environmental gradients. Results: Two main environmental gradients affecting the plant community structure were identified within the drawdown zone; these were a vertical and longitudinal gradient. On the vertical dimension, a hydrological gradient of flood/exposure, the annual-dominated plant community near the water edge changed to a perennial-dominated community at the highest elevation. On the longitudinal dimension from the dam to the upstream, plant species composition changed from an upland forest-edge community to a lowland riverine community, and this was correlated with slope degree, soil particle size, and soil moisture content. Simultaneously, the composition of the soil seedbank was separated along the vertical gradient of the drawdown zone, with mainly annuals near the water edge and some perennials at higher elevations. The species composition similarity between the seedbank and extant vegetation was greater in the annual communities at low elevation than in the perennial communities at higher elevation. Conclusions: The structures of plant community and soil seedbank in the drawdown zone of a monsoonal riverine reservoir were changed first along the vertical and secondly along the longitudinal gradients. The soil seedbank could play an important role on the vegetation regeneration after the disturbances of flood/exposure in the drawdown zone. These results indicate that it is important to understand the vertical and longitudinal environmental gradients affecting shoreline plant community structure and the role of soil seedbanks on the rapid vegetation regeneration for conserving and restoring the drawdown zone of a monsoonal reservoir.

A Comparative Study on the Habitat of Abies koreana Wilson between Mt. Jiri and Mt. Halla

  • lhm, Byung-Sun;Lee, Jeom-sook;Kim, Moon-Hong;Kim, Ha-Song
    • Plant Resources
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    • v.3 no.2
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    • pp.138-147
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    • 2000
  • This examination of vegetation is conducted from June to Oct. 1999 through on the spot survey, centering on the habitat of Abies koreana around Imgeolryeong, Jangteomok, and Jeseokbong in Mt Jiri and Yeongsil path and Seongpanak path in Mt. Halla. Species composition tables of the Abies koreana community by altitude and slope in Mt. Jiri and Mt. Halla are made based on the community composition tables examined in quadrat. The Abies koreana-Saso quelpaertensis community in a west slope of Mt. Halla is found that Abies koreana of 4-6m in height forms subtree layer and that of 8-9m in height the tree layer and it reflects a difference between community structure by slope and main composition species. While the tree layer of Abies koreana community is 12-14 in height around the area of 1,290-1,560m above the sea of Imgeolryong and path from Baekmudong to Jangteomok, it is 8-12m in height in the area of 1,680-1,780m above the sea of path from Jangteomok to Jeseokbong. It means that community structure depends on area and attitude. This study finds out that commonly appearing composition species similar to coverage and presence are Lepisorus thunberianus, Quercus mongolica, Solidago virga-aurea var. asiatica, Ligularia fischeri, Carex lanceolata, Clintonia udensis, Magnolia sieboldii, Betula ermani, Acer pseudo-sieboldianum. As soil environment of surveyed area, pH of surveyed spots is similar in Mt. Jiri and Mt. Halla, electrical conductivity is higher in Mt Jiri, and contents of organic matter is relatively higher in a west slope of Mt. Jiri and Mt. Halla and lower in their south and west slopes. Contents of organic matter and total nitrogen show that the area of 1,550m above the sea in a west slope of Mt. Halla is some higher. For pH and contents of total nitrogen and organic matter, Mt. Halla is higher than Mt. Jiri but for electrical conductivity, Mt. Jiri is relatively higher than Mt. Halla.

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Effect of Bacterial Wilt on Fungal Community Composition in Rhizosphere Soil of Tobaccos in Tropical Yunnan

  • Zheng, Yuanxian;Wang, Jiming;Zhao, Wenlong;Cai, Xianjie;Xu, Yinlian;Chen, Xiaolong;Yang, Min;Huang, Feiyan;Yu, Lei;He, Yuansheng
    • The Plant Pathology Journal
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    • v.38 no.3
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    • pp.203-211
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    • 2022
  • Bacterial wilt, which is a major soil-borne disease with widespread occurrence, poses a severe danger in the field of tobacco production. However, there is very limited knowledge on bacterial wilt-induced microecological changes in the tobacco root system and on the interaction between Ralstonia solanacearum and fungal communities in the rhizosphere soil. Thus, in this study, changes in fungal communities in the rhizosphere soil of tobaccos with bacterial wilt were studied by 18S rRNA gene sequencing. The community composition of fungi in bacterial wilt-infected soil and healthy soil in two tobacco areas (Gengma and Boshang, Lincang City, Yunnan Province, China) was studied through the paired comparison method in July 2019. The results showed that there were significant differences in fungal community composition between the rhizosphere soil of diseased plants and healthy plants. The changes in the composition and diversity of fungal communities in the rhizosphere soil of tobaccos are vital characteristics of tobaccos with bacterial wilt, and the imbalance in the rhizosphere microecosystem of tobacco plants may further aggravate the disease.

Community Structure of forest vegetation in Mt. Bislsan (비슬산(琵瑟山) 산림식생(山林植生)의 군락구조(群落構造))

  • Lee, Jung-Hyo;Suh, Seung-Hee;Hong, Sung-Cheon
    • Current Research on Agriculture and Life Sciences
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    • v.23
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    • pp.9-18
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    • 2005
  • Vegetation composition and structure of forest community at Mt. Bislsan, Dalseung-Gun, Daegu in Korea, were studied using a qualitative with a quantitative approach and its vegetation types and various ecological characteristics such as the importance values, species diversity of the major component species analyzed. The forest vegetation were classified into 2 community group, 14 community, 6 group, and total of 18 vegetation units. Pinus densiflora distributed mainly from lower at the sea level, while Quercus mongolica tended to distributed upper altitude in Physiognomical vegetation. the species diversity values showed mostly 0.8 and Quercus dentata, Quercus serrato and Cornus controversa Community and so on highly showed to 1.0 and 1.1. According to the results of importance value analysis, the I.V. of pinus densiflora and Quercus mongolica highly showed in the tree and subtree layer, and Rhododendron mucronulatum and Lindera obtusiloba and so on highly showed in the shrub.

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